Fuel tanks are often employed to provide fuel to engines, such as internal combustion engines, diesel engines, combustion engines, and the like. In many cases, the fuel tanks, as well as the engines, are mobile. For example automobile engines and lawn mower engines include a fuel tank that is permanently attached to and moves with the automobile or the lawn mower.
Other fuel tanks remain stationary and serve to store fuel for use in one or more stationary applications. For example, farms often include a large fuel tank that stores fuel that can be used with vehicles, tractors, lawn equipment, snow equipment, and the like. Another example of a detachable fuel storage tank is a fuel tank used in marine applications. Thus, the fuel tank does not have a permanent connection between it and an engine. Rather, an outlet from the tank allows fuel to be drawn from the tank and delivered to the desired location.
Stationary tanks may be subjected to daily ambient temperature changes that may cause the release of hydrocarbons or gasoline. Such emissions are known as “diurnal” emissions. Fuel tanks are typically vented to the atmosphere to prevent pressure buildup in the tank.